Analysis of Sulfur Compound Species

Importance of Topic

Sulfur-containing compounds play critical roles in petroleum, food, environmental monitoring, and chemical manufacturing. Their low concentrations and toxic or odorous nature demand sensitive and selective detection methods to ensure compliance with safety, quality, and regulatory standards.

Objectives and Overview of Study

This application note demonstrates the analysis of eleven model sulfur species using gas chromatography coupled with a sulfur chemiluminescence detector. The aim is to evaluate relative molar sensitivity across compounds such as thiophene, dimethyl disulfide, and diallyl disulfide under optimized conditions.

Methodology and Instrumentation

Samples of eleven sulfur compounds at 10 micrograms per milliliter were injected in split mode to achieve chromatographic separation on a nonpolar SH-1 column. Key chromatographic parameters included an injector temperature of 220 °C, split ratio of 1 to 50, and helium carrier gas at a linear velocity of 30 centimeters per second. The column temperature program ranged from 50 °C initial hold to 250 °C final temperature. Detection was performed by a sulfur chemiluminescence detector using a reactor temperature of 850 °C and gas flows of hydrogen, nitrogen, oxygen, and ozone for selective reaction and signal generation.

Used Instrumentation

• Gas chromatograph Nexis GC-2030 with AOC-20i Plus auto-injector
• Sulfur chemiluminescence detector SCD-2030
• SH-1 capillary column 30 m by 0.25 mm id, 0.25 µm film thickness
• Split injection unit treated with Sulfinert for reduced adsorption

Main Results and Discussion

All eleven sulfur species were baseline separated within the optimized run time, exhibiting distinct response factors in the chemiluminescence detector. Compounds with simpler structures such as thiophene showed higher sensitivity, whereas larger polysulfides exhibited slightly lower molar responses due to reaction kinetics in the detector. The results confirm the method's broad applicability for diverse sulfur analytes and highlight the need to apply individual response factors for accurate quantification.

Benefits and Practical Applications

The developed GC-SCD method provides high selectivity for sulfur species, reducing interferences from non-sulfur matrix components. Laboratories in petrochemical quality control, environmental monitoring, and food analysis can implement this protocol to achieve reliable quantification of trace sulfur compounds. The use of Sulfinert-treated injection liners further minimizes sample loss and improves reproducibility.

Future Trends and Opportunities

Emerging trends point to integrating this approach with multidimensional chromatography or mass spectrometry to enhance compound identification while retaining sulfur specificity. Advances in detector miniaturization and real-time field deployable systems may extend applications to onsite monitoring in industrial plants and environmental sites. Further research on detector reaction chemistry could improve sensitivity for refractory sulfur species.

Conclusion

This work validates a robust GC-SCD method for comprehensive analysis of key sulfur compounds. The combination of optimized chromatographic separation and chemiluminescence detection ensures sensitive, selective, and reproducible results, meeting the demands of diverse analytical laboratories.

Reference

• Shimadzu Corporation Application News G330 Analysis of Sulfur Compound Species by GC-SCD using SH-1 Column First Edition September 2022